Narrative:

On sep/xx/94 shortly after takeoff we were notified by the flight attendant that our right outbound engine cowl had popped open. Visual inspection confirmed this. We declared an emergency and returned to the airport without any problems. Events: we returned to stl at XA40 am for our last round trip of a 2-DAY trip which had a scheduled departure time of XB27 am. At approximately XC15 am with one passenger on board (wheelchair passenger) we were notified by flight operations that they were switching us to another aircraft, so that they could use our aircraft for a flight that had already been delayed and which we were told had priority. I understand this to mean they had more passenger going to the other destination than our 13 passenger. The aircraft we were switched to was having maintenance repair and an advise time of XD30 am. We preflted this aircraft and waited. At approximately XD35 am we were notified that we were again being switched to another aircraft. We did our preflight walkaround followed by our first flight of the day checks because this aircraft had been in the maintenance hangar for scheduled maintenance on sep/xx/94. It appears that maintenance personnel did not properly secure the right outbound engine cowl. This was not obvious by visual inspection by the captain and myself. Unfortunately, I did not tug on the cowl to check its security (something I will now do). I feel that after waiting over 3 hours to depart, having to preflight 3 different aircraft, having already been delayed for over an hour from our scheduled departure time, and suddenly feeling pressured to expedite our departure had contributed to this incident.

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Original NASA ASRS Text

Title: COMMUTER ACFT HAS ENG COWL OPEN IN FLT. RETURN LAND.

Narrative: ON SEP/XX/94 SHORTLY AFTER TKOF WE WERE NOTIFIED BY THE FLT ATTENDANT THAT OUR R OUTBOUND ENG COWL HAD POPPED OPEN. VISUAL INSPECTION CONFIRMED THIS. WE DECLARED AN EMER AND RETURNED TO THE ARPT WITHOUT ANY PROBS. EVENTS: WE RETURNED TO STL AT XA40 AM FOR OUR LAST ROUND TRIP OF A 2-DAY TRIP WHICH HAD A SCHEDULED DEP TIME OF XB27 AM. AT APPROX XC15 AM WITH ONE PAX ON BOARD (WHEELCHAIR PAX) WE WERE NOTIFIED BY FLT OPS THAT THEY WERE SWITCHING US TO ANOTHER ACFT, SO THAT THEY COULD USE OUR ACFT FOR A FLT THAT HAD ALREADY BEEN DELAYED AND WHICH WE WERE TOLD HAD PRIORITY. I UNDERSTAND THIS TO MEAN THEY HAD MORE PAX GOING TO THE OTHER DEST THAN OUR 13 PAX. THE ACFT WE WERE SWITCHED TO WAS HAVING MAINT REPAIR AND AN ADVISE TIME OF XD30 AM. WE PREFLTED THIS ACFT AND WAITED. AT APPROX XD35 AM WE WERE NOTIFIED THAT WE WERE AGAIN BEING SWITCHED TO ANOTHER ACFT. WE DID OUR PREFLT WALKAROUND FOLLOWED BY OUR FIRST FLT OF THE DAY CHKS BECAUSE THIS ACFT HAD BEEN IN THE MAINT HANGAR FOR SCHEDULED MAINT ON SEP/XX/94. IT APPEARS THAT MAINT PERSONNEL DID NOT PROPERLY SECURE THE R OUTBOUND ENG COWL. THIS WAS NOT OBVIOUS BY VISUAL INSPECTION BY THE CAPT AND MYSELF. UNFORTUNATELY, I DID NOT TUG ON THE COWL TO CHK ITS SECURITY (SOMETHING I WILL NOW DO). I FEEL THAT AFTER WAITING OVER 3 HRS TO DEPART, HAVING TO PREFLT 3 DIFFERENT ACFT, HAVING ALREADY BEEN DELAYED FOR OVER AN HR FROM OUR SCHEDULED DEP TIME, AND SUDDENLY FEELING PRESSURED TO EXPEDITE OUR DEP HAD CONTRIBUTED TO THIS INCIDENT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.